CVE-2026-123571
Published:November 08, 2026
Updated:November 09, 2026
Hickory DNS from 0.26.0 before 0.26.2 contains an integer underflow vulnerability in TSIG RDATA decoding that allows remote attackers to trigger a panic via malformed records. Attackers can send a crafted TSIG record in DNS wire format to cause unchecked subtraction underflow, crashing builds with overflow checks enabled and causing denial of service.
Affected Packages
https://github.com/hickory-dns/hickory-dns.git (GITHUB):
Affected version(s) >=v0.26.0-beta.2 <v0.26.2Fix Suggestion:
Update to version v0.26.2hickory-proto (RUST):
Affected version(s) >=0.26.0-beta.2 <0.26.2Fix Suggestion:
Update to version 0.26.2Related Resources (4)
Do you need more information?
Contact UsCVSS v4
Base Score:
8.7
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
NONE
Vulnerable System Availability
HIGH
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
7.5
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Weakness Type (CWE)
Integer Underflow (Wrap or Wraparound)
EPSS
Base Score:
0.41